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Related papers: Spectral classification

200 papers

The solar spectrum conveys most of our diagnostics to find out how our star works. They must be understood for utilization, but solar spectrum formation is complex because the interaction of matter and radiation within the solar atmosphere…

Solar and Stellar Astrophysics · Physics 2022-08-16 Robert J. Rutten

Over the next few years new spectroscopic surveys (from the optical surveys of the Sloan Digital Sky Survey and the 2 degree Field survey through to space-based ultraviolet satellites such as GALEX) will provide the opportunity and…

Astrophysics · Physics 2009-10-31 A. J. Connolly , A. S. Szalay

Optical spectroscopic monitoring has been conducted of two O stars in the Small and one in the Large Magellanic Cloud, the spectral characteristics of which place them in the Of?p category, which has been established in the Galaxy to…

We have determined new statistical relations to estimate the fundamental atmospheric parameters of effective temperature and surface gravity, using MK spectral classification, and vice versa. The relations were constructed based on the…

Solar and Stellar Astrophysics · Physics 2020-09-30 O. Yu. Malkov , D. A. Kovaleva , S. G. Sichevsky , G. Zhao

In the last two decades about a dozen methods were invented which derive, from a series of composite spectra over the orbit, the spectra of individual components in binary and multiple systems. Reconstructed spectra can then be analyzed…

Solar and Stellar Astrophysics · Physics 2009-09-18 K. Pavlovski , H. Hensberge

Stellar multiplicity is an ubiquitous outcome of the star formation process. Characterizing the frequency and main characteristics of multiple systems and their dependencies on primary mass and environment is therefore a powerful tool to…

Solar and Stellar Astrophysics · Physics 2016-11-04 Gaspard Duchêne , Adam Kraus

In this paper we investigate the power of spectral synthesis as a mean to estimate physical properties of galaxies. Spectral synthesis is nothing more than the decomposition of an observed spectrum in terms of a superposition of a base of…

Astrophysics · Physics 2010-04-06 R. Cid Fernandes , A. Mateus , L. Sodre , G. Stasinska , J. M. Gomes

Spectral measures arise in numerous applications such as quantum mechanics, signal processing, resonances, and fluid stability. Similarly, spectral decompositions (pure point, absolutely continuous and singular continuous) often…

Spectral Theory · Mathematics 2021-03-02 Matthew John Colbrook

The cosmic ray energy distributions contain spectral features, that is narrow energy regions where the slope of the spectrum changes rapidly. The identification and study of these features is of great importance to understand the…

High Energy Astrophysical Phenomena · Physics 2017-12-27 Paolo Lipari

We present a quantitative method to classify galaxies, based on multi-wavelength data and elaborated from the properties of nearby galaxies. Our objective is to define an evolutionary method that can be used for low and high redshift…

Astrophysics · Physics 2017-03-29 Sebastien Lauger , Denis Burgarella , Veronique Buat

We describe a technique for deriving effective temperatures, surface gravities, rotation velocities, and radial velocities from high resolution near-IR spectra. The technique matches the observed near-IR spectra to spectra synthesized from…

Astrophysics · Physics 2009-11-10 G. W. Doppmann , D. T. Jaffe

This article introduces a novel approach to the classification of categorical time series under the supervised learning paradigm. To construct meaningful features for categorical time series classification, we consider two relevant…

Methodology · Statistics 2021-02-05 Zeda Li , Scott A. Bruce , Tian Cai

Theoretical stellar spectra rely on model stellar atmospheres computed based on our understanding of the physical laws at play in the stellar interiors. These models, coupled with atomic and molecular line databases, are used to generate…

Solar and Stellar Astrophysics · Physics 2020-07-01 Kaushal Sharma , Harinder P. Singh , Ranjan Gupta , Ajit Kembhavi , Kaustubh Vaghmare , Jianrong Shi , Yongheng Zhao , Jiannan Zhang , Yue Wu

We investigate the power of spectral synthesis as a mean to estimate physical properties of galaxies. Spectral synthesis is nothing more than the decomposition of an observed spectrum in terms of a superposition of a base of simple stellar…

Astrophysics · Physics 2007-05-23 L. Sodre , R. Cid Fernandes , A. Mateus , G. Stasinska , J. M. Gomes

The phenomenon of spectral mimicry refers to the fact that hypergiants and post-AGB supergiants - stars of different masses in fundamentally different stages of their evolution have similar optical spectra, and also share certain other…

Solar and Stellar Astrophysics · Physics 2018-03-14 V. G. Klochkova , E. L. Chentsov

The Spectral Galaxy Pairs (SGPs) are defined as the composite galaxy spectra which contain two independent redshift systems. These spectra are useful for studying dust properties of the foreground galaxies. In this paper, a total of 165…

Astrophysics of Galaxies · Physics 2016-11-04 Haifeng Yang , Ali Luo , Xiaoyan Chen , Jifu Zhang , Wen Hou , Jianghui Cai , Peng Wei , Juanjuan Ren , Xiaojie Liu , Yongheng Zhao

The method of spectral disentangling has now created the opportunity for studying the chemical composition in previously inaccessible components of binary and multiple stars. This in turn makes it possible to trace their chemical evolution,…

Solar and Stellar Astrophysics · Physics 2015-05-30 K. Pavlovski , J. Southworth

The optical and infrared spectra of a wide variety of `cool' astronomical objects including the Sun, sunspots, K-, M- and S-type stars, carbon stars, brown dwarfs and extrasolar planets are reviewed. The review provides the necessary…

Solar and Stellar Astrophysics · Physics 2010-11-11 Peter F. Bernath

The taxonomic classification of asteroids has been mostly based on spectroscopic observations with wavelengths spanning from the VIS to the NIR. VIS-NIR spectra of $\sim$2500 asteroids have been obtained since the 1970s; the SDSS MOC 4 was…

Earth and Planetary Astrophysics · Physics 2022-08-10 Dong-Goo Roh , Hong-Kyu Moon , Min-Su Shin , Francesca E. DeMeo

In recent years, the development of spectropolarimetric techniques deeply modified our knowledge of stellar magnetism. In the case of solar-type stars, the challenge is to measure a geometrically complex field and determine its evolution…

Astrophysics · Physics 2007-05-23 P. Petit